Abstract
It has been reported that yellow tinted lenses increase the pupil size and it is questionable, if the resulting pupillary light response (PLR) influences the visual performance. The PLR reflects not only the amount of light entering the eye, but also cognitive factors such as visual attention and awareness. The aim of this study was to investigate the relation between pupil response and the presence of an acoustic feedback on contrast sensitivity (CS) measurements under tinted lenses. A CS-test determined the threshold contrast using a sine wave grating at 0.5, 1.5, 3 and 6 cycle per degree each with 50 trials. This CS-test included an adaptive staircase (Ψ-method), a 16-bit gray-level resolution and acoustic feedback indicating correctness. The stimulus was surrounded by a white annular scatter source (adapted from Oculus C-Quant) in order to induce a PLR recorded with an eye-tracker (EyeLink-1000-Plus). CS and PLR were measured monocularly in five experienced participants wearing orange, green, violet and yellow tinted lens under equi-luminant conditions. The relative PRL was averaged over participants and tested spatial frequencies. Relative PLR amplitude was significantly different (p < 0.001) in an ANOVA for the conditions with and without acoustic feedback. In conditions with feedback, this difference in relative PLR was larger for orange and yellow tinted lenses compared to no filter conditions (p < 0.01). The CS measured with acoustic feedback showed no significant improvement compared to no-feedback conditions (p=0.12), although this could be expected due to attentional fluctuations and PLR change. However, there was a tendency for an impact of feedback on CS at lower spatial frequencies. This study suggests a positive relation between pupil response and acoustic feedback during contrast sensitivity measurements. In conclusion, orange and yellow tinted lenses showed a larger PLR, suggesting a direct attentional effect of acoustic feedback on pupil response.
Meeting abstract presented at VSS 2017